Statuspage allows page admins to export a list of all subscribers in either JSON or CSV format. To do this, log into your account, and select Notifications from the left-hand navigation bar.
From the dropdown menu, select 'Export Subscribers'. A pop up menu will appear, with two sets of options available. On the left side, you can select which subscriber types you would like to export (email, sms, or webhook), and on the right side you'll select whether you would like the results sent to you in CSV or JSON format.
After you've selected your options, click on 'Export Subscribers', and your results will be emailed to you shortly.